Wednesday 22 December 2010 09.36 EST
First published on Wednesday 22 December 2010 09.36 EST

Having broken records for advance orders in the US, Call of Duty: Black Ops today crossed the $1bn (£648m) sales mark – less than six weeks after release.

The game's publisher, Activision, said Black Ops raked in more than $650m (£420m) worldwide within five days of going on sale, outstripping last year's Call of Duty: Modern Warfare 2 by $100m (£65m) in the same period.

"In all of entertainment, only Call of Duty and Avatar have ever achieved the billion-dollar revenue milestone this quickly," Activision chief executive Bobby Kotick said. James Cameron's Avatar became the fastest movie to reach the $1bn mark in December last year, taking the highest-grossing film in history award away from Titanic.

However, the highly successful game series also today became the epicentre of a $400m (£256m) legal fight, as Activision charged Electronic Arts (EA) with hijacking the company's assets and threatening the Call of Duty franchise.

Activision added EA to its counter-lawsuit against two of its former executives who helped develop Call of Duty, claiming the pair broke an exclusive contract agreement when they left the company in March to develop games for EA and set up their own company.

More than 600m hours of gaming time has been logged on Black Ops since its launch on 9 November, Activision said, and the average player logs on every day for more than an hour at a time.

Game Group, owner of more than 1,300 Game and Gamestation high-street stores in the UK, has been boosted by the release of Black Ops and Fifa 11 in the final quarter. Discount promotions on Black Ops, which it sold at half price to customers who bought another chart title or traded in another game at the same time, had been successful, the retailer claimed earlier this month.